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United States Patent | 5,761,638 |
Knittle ,   et al. | June 2, 1998 |
The present invention provides a telephone network apparatus for performing speech recognition services in a telephone system in substantially real time. The apparatus uses a telephone channel signal to determine the echo delay of a telephone channel and then uses this delay to configure an echo cancellation filter for use in performing speech recognition. Use of echo delay in configuring the filter allows the echo cancellation function to be done using much less computational time than would be needed without its use, thereby granting a speech recognition unit greater access to a resident microprocessor to perform its function in substantially real time.
Inventors: | Knittle; Curtis D. (1585 S. Ptikin Ave., Superior, CO 80027); Jaramillo; Paul D. (5654 W. 75th Ave., Arvada, CO 80003); Wu; Frank H. (253 Lois Cir., Louisville, CO 80027) |
Appl. No.: | 406352 |
Filed: | March 17, 1995 |
Current U.S. Class: | 704/233; 379/88.01; 379/406.03 |
Intern'l Class: | G10L 005/06; G10L 009/00; H04M 001/64; H04M 001/00 |
Field of Search: | 370/32.1 379/88,67,410,411 704/233 |
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